Settable tiles have been used at present in many processes for covering dwellings. These tiles are generally constituted of baked clay permitting obtaining coverings that are quite sealed and resistant but heavy and exposed to breakage, in particular in the case of hail. There has accordingly appeared on the market, as a roof covering, plates of synthetic material on which has been stamped the shape of interfitting tiles. These lightweight plates, resistant to the weather, have nevertheless not been entirely a commercial success, essentially for two reasons. On the one hand, the use of materials such as Fibrociment (trademark), is dangerous to the health of users. On the other hand, these plates only badly imitate the natural appearance of conventional materials, such as tiles and slates, this poor imitation being moreover by a rapid degradation with time of their appearance.
Solutions of the first problem set forth above have been found and are set forth particularly in French patents FR-A-2.451.429 and FR-A-2.522.348. The roofing elements described in these patents are obtained by use of reinforced resins that do not risk the health of the occupants of a dwelling. However, the composition of such roofing elements and the processes for production are not satisfactory in terms of appearance of the product and in terms of long-term strength of this product.
The patent FR-A-2.522.348 teaches, to imitate the appearance of traditional products, the use of granulates which give rise to problems of homogeneity of the mixture and of the distribution of the granulates on the surface of the final product.
The patent FR-A-2.451.429 relates itself to the use of a colored GELCOAT having a rough appearance adapted to give rise to a certain number of drawbacks such as retention of dirt and the growth of moss in its roughened surface.
The patent FR-A-2.363.195 relates essentially to the production of a production mold in polyester or other thermal hardenable substance from a core clad with a plastic or hydraulic coating. This patent also describes a process for mass production of pieces by such a mold. This process comprises a step of cladding one wall of the mold with a colored GELCOAT, then a step of cladding this mold with a mixture of resin plus fibers. The GELCOAT could be present in the form of a continuous layer or in the form of specks of different colors. Such a document corresponds to the conventional production of a closed covering element of two layers, one constituting the core of the element, the other formed by a GELCOAT that gives long-term strength.